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16
Heating Test
The heating (
HEAT
) submenu is used to change output status
for the individual heat stages, gas or electric. The fans (
FANS
)
and cooling (
COOL
) service test outputs are reset to OFF for
the heating service test. Indoor and outdoor fans are controlled
normally to maintain proper unit operation. All normal heating
alarms and alerts are functional.
NOTE: Field terminal board terminal R must be connected to W1
for the heat to operate in service test. Alert number T410 will oc-
cur as a reminder if not done. If the normal unit control mode is
thermostat mode, then remove the R-W1 jumper after completing
service test.
THIRD PARTY CONTROL
Third party controls may interface with the unit
Comfort
Link
controls through the connections described below. See other
sections of these instructions for more information on the relat-
ed unit control and configurations.
Cooling/Heating Control
The thermostat inputs are provided on the field connection ter-
minal board. The Unit Control Type configuration,
Configura-
tion
UNIT
U.CTL
, must be 2 to recognize the below in-
puts. Terminal R is the 24vac source for the following:
• Y1 = First stage cooling
• Y2 = Second stage cooling
• W1 = First stage heating
• W2 = Second stage heating
• G = Indoor fan
Dehumidification Control
On HumidiMiZer units the HUM terminal is provided on the
field connection terminal board. Humidity Switch configura-
tion,
Configuration
UNIT
RH.SW
, identifies the normally
open or normally closed status of this input at HIGH humidity.
NOTE: Dehumidification is considered a cooling function in the
software.
Remote Occupancy
The remote occupancy input is provided on the field connection
terminal board (TB). The Remote Occupancy Switch configura-
tion,
Configuration
UNIT
RM.SW
, identifies the normally
open or normally closed status of this input when unoccupied.
• RMOL = 24 VAC signal input
• R-2 = 24 VAC source for dry contact
Fire Shutdown
The fire shutdown input is provided for unit shutdown in re-
sponse to a fire alarm or smoke detector. The Fire Shutdown
Switch configuration,
Configuration
UNIT
FS.SW
, identi-
fies the normally open or normally closed status of this input
when there is no fire alarm.
• FDWN = 24 VAC signal input
Alarm Output
The alarm output is provided on the field connection terminal
board to indicate a current alarm status. The output will be
24VAC if a current alarm exists.
• C-2 = 24 VAC common
• X = 24 VAC signal output
Economizer Damper Control
For units with the economizer option or accessory and the ECB
control board, the damper position can be directly controlled
through the IAQ sensor input provided on the field connection
terminal board. The IAQ Analog Input configuration,
Configuration
AIR.Q
IA.CF
will have to set to 3 (Control
Minimum Position). When
IA.CF
= 3, an external 4 to 20 mA
source is used to move the damper 0% to 100% directly.
IAQ = 4-20mA + signal
COM = 4-20mA - common
NOTE: In this mode, preset minimum positions configurations
are not valid, the damper position may exceed the input posi-
tion to provide economizer cooling and CO
2
sensor input can
not be used for DCV control. Refer to the Indoor Air Quality
operation section on page 27 for more information.
CONTROLS OPERATION
Display Configuration
The
Configuration
DISP
submenu is used to configure the
local display settings.
Metric Display (METR)
This variable is used to change the display from English units
to Metric units.
Language Selection (LANG)
This variable is used to change the language of the Com-
fortLink display. At this time, only English is available.
Password Enable (PROT)
This variable enables or disables the use of a password. The
password is used to restrict use of the control to change config-
urations.
Service Password (PSWD)
This variable is the 4-digit numeric password that is required if
enabled.
Test Display LEDs (TEST)
This is used to test the operation of the
Comfort
Link display.
Unit Configuration
Many configurations that indicate what factory options and/or
field accessories are installed and other common operation
variables are included in Unit Configuration (
Configura-
tion
UNIT
). These configurations will be set in the factory
for the factory-installed options (FIOPs). Field-installed acces-
sories installed will require configuration changes. General
unit and fan control configurations are also covered under this
Unit Configuration menu.
Start-Up Delay (S.DLY)
This configuration sets the control start-up delay after the pow-
er is interrupted. This can be used to stagger the start-up of
multiple units.
Unit Control Type (U.CTL)
This configuration defines if temperature control is based on
thermostat inputs or space temperature sensor input.
•
U.CTL
= 2 (Thermostat) — The unit determines cooling
and heating demand by the state of G, Y1, Y2,W1, and W2
inputs from a space thermostat. This value is the factory
default.
•
U.CTL
= 3 (Space Sensor) — The unit determines cooling
and heating demand based on the space temperature and
the appropriate set point. Used also as Linkage configura-
tion. The jumper wire in the installer’s packet must be con-
nected between R and W1 on the low voltage terminal
board for heating mode to operate.
THERMOSTAT CONTROL TYPE (T.CTL)
This configuration applies only if Unit Control Type is Thermo-
stat (
Configuration
Unit
U.CTL = 2
). The value determines
alternative cooling and Humidi-MiZer circuit staging. See the
Cooling and Humidi-MiZer sections for more information. The
factory default value is
T.CTL = 0
(Adaptive).
Summary of Contents for /50HC 04-28
Page 69: ...69 Fig 24 Typical Control Diagram for 48HC 04 14 Units 48HC 08 09 shown ...
Page 70: ...70 Fig 25 Typical Power Diagram for 48HC 04 14 Units 48HC 08 09 shown ...
Page 71: ...71 Fig 26 Typical Control Diagram for 50HC 04 14 Units 50HC 14 shown ...
Page 72: ...72 Fig 27 Typical Power Diagram for 50HC 04 14 Units 50HC 14 Non Humidi MiZer shown ...
Page 73: ...73 Fig 28 Typical Control Diagram 48HC 17 28 Units ...
Page 74: ...74 Fig 29 Typical Control Diagram 50HC 17 28 Units ...
Page 75: ...75 Fig 30 Typical Humid MiZer Power Diagram and Component Arrangement 48 50HC 17 28 Units ...
Page 76: ...76 Fig 31 Typical Non Humid MiZer Power Diagram and Component Arrangement 48 50HC 17 28 Units ...
Page 89: ...89 Fig 42 Modulating ERV Wiring Schematic ...
Page 90: ...90 Fig 43 EnergyX ERV Control Box Component Layouts ...
Page 101: ...101 Fig 59 Exhaust Fan Assembly Removal Exhaust Fan Assembly ...
Page 141: ......